Error, authentication required

I found similar questions to this and followed the advice without much success.

I am writing my first app and I am adding inapp purchases. When "mHelper.launchPurchaseFlow" is called an application, the message box "Error, authentication required. You need to log in to your Google account is displayed.

I came in. I tried to delete the account and restore it. I tried to create a new account and use it instead. I tried the app on two different tablets with the same result.

Here is an example of my code. The purchase item is configured in my google developer console. My code only calls "buy_two_stars" after it mHelper.startSetup()

returns success.

The value in the variable purchaseprogress

indicates that it never goes through the function buy_two_stars()

:

public void buy_two_stars()
{
    mHelper.launchPurchaseFlow(this,"item_stars",1001,purchasedit,"");
    PurchaseProgress=0;
}



IabHelper.OnIabPurchaseFinishedListener purchasedit=new IabHelper.OnIabPurchaseFinishedListener() {

@Override
public void onIabPurchaseFinished(IabResult result, Purchase info) 
{
    if(result.isFailure())
    {
        PurchaseProgress=-1;
    }
    else if(info.getSku().equals("item_stars") )
    {
        purchaseditem=info;
        mHelper.consumeAsync(info,consumerfunc);
        PurchaseProgress=1;
    }   
}
};
IabHelper.OnConsumeFinishedListener consumerfunc=new IabHelper.OnConsumeFinishedListener() 
{

    @Override
    public void onConsumeFinished(Purchase purchase, IabResult result) {
    if(result.isFailure())
    { 
        PurchaseProgress=-1;
    }
    else 
    {
        PurchaseProgress=0;
    }   
}
};

      

        
        
        
      

    

many thanks.